I have to say that if I have a horse that spooks to bolt I prefer to work at removing their inclination to do it than to put stronger brakes on them - though that's OK in the short term I suppose if its a step towards a cure - but I don't see the bit as the cure in itself - because the spook is still there
It seems like their are two trains of thought.....
Ride him enough and it will eventually go away through experience
Desensitize to stimulus on the ground. Which actually he is VERY good at. I've been draping tarps and such over him since he was a baby. I can even put a tarp over his head. But all bets are off when something pops out on the trail. It seems to be the sudden pop-outs that get him. Although the other day when the dogs came we both saw them coming, he just lost his marbles when they came straight at him.
Sigh. I am very open to suggestions. I can't seem to catch him before his spins either. It happens quicker than I can seem to catch him.
Maybe I need to start another thread on this subject.